Centrifugal brake mechanism.



A. c. COBB.

CENTHIFUGAL BRAKE MEGHAN|SM. APPLICATION FILED MAR. 1.0, 1914.' RENEWED SEPTH, 1917.

1,263,041.` Patented Apr. 16, 1918. l

\\"/ i* ,l I Q Q vx m l n o n T- "Q R1# .n j ,Uu I y||v lo om? t@ v l gjqwmtu @MQW @Mmmm Hitman/w19 msn-misma. mmc. ummm u PA f ENT ernten f 1 CENTRIFUGAL BRAKE MEoHANisM.

Specification of Letters Patent.

Patented apr. 1e, 1918.

applicatibn'aiee march 1o, 1914, serial No. 823,780. Renewed september 11, 1917. serial No. 190,868.

" 'lf-hall it may concern:-

'Be Ait known that I, ALBERT C. Conn, citii zen ofthe United States, residing at -Hous'- ton, in the county Texas, have invented certain new and useful 'Improvements in Centrifugal Brake Mechanism, of which the following is a specificamechanism soarranged'. upon the elevatorl A This invention relates to centrifugal brakey mechanism designedprimarily for use upon elevators, and has for its object to provide car or'cage as to be-actuatable at apredetermg specification and then more particularly mined speed of rotation during normal movement of said'car, said mechanism however, being so constructed as to, should the car travel at an abnormal rate of speed,v gradually and automatically increase its speed and causean automatic brake device vtdi-be plled and set.

A further object of the'invention iste So\ arrange a plurality of i'ntermeshing gears with respect to a stationary rack\as' to cause one of said gears, in the event of the loss of the elevator control, to rotate at an eX- 'ceedingly high rate of4 speed, whereby tod .correspondingly rotate a suitable governor having connection with and controlling'operation of the above mentioned brake device.

The invention still further aims to provide an exceedingly simple, practical and4 Aefiicient device wherein the component parts, except'the rack aforesad, are suitably 1ncasedand arranged conveniently beneath the loorof, the elevator car or cage.- The, above and additional objects are ac-. complishedlby such means as are illustrated in their preferred embodiment 1n the accom# panying drawings, described in the fellowlnted o ut in the claims which are append-- drawings WhereinI have illustrated my improved centrifugal brake. v.Referringnow to the drawings by 11umera ls,'2 designates asian entiretylthe, elevator shaft, and 4, as an entirety, a two-part casing within which the: centrifugal .brake mechanism comprising the presentinvention isv arranged. Said'l casing 4 is adapted for securement in anysuitabl'e manner upon the underside -of the elevator ear (not shown), preferably at one side thereof.

of Harris and State of A' -with teeth'lO, the

v 12 journaled within 'and form a part of thisapplicag 'tation' 'with t shaft 24. The

A-rail 7, carrying a rack bar 8, isxedly secured as indicated at 9 to the rearv wall of the elevator shaft. The respective longitudinal edgesof the rack bar 8 -'areprovided teeth upon oney lside or edge of theisaid bar being adapted to mesh with a gear 11 mounted upon asuitable shaft the' casing 4 previously referred to.. lThe teeth upon the opposite edge'of the rack bar8 mesh into a like gear 13 mounted upon a. second shaft 14 also journaled Within the said casing 4. The above arrangement will provide, during movement of theelevator car or cage, for

the rotation of the said gears .11 and 13 in.

opposite directions. Said shaft`12 carries a--comparatively large'gear 15 whil'e'the4` shaft 14 carries a similar gear 16, the teeth lof. the: saidgears 15 and 1G being adapted for meshing lengagement as is clearly Aillustrated in the drawings. A third shaft 17 is journaled within the casing 4, said shaft carrying a pinion 18 meshing into thev gear 16 above noted. A comparatively large gear I1,9 is mounted upon the shaft 17, said last mentioned gear meshing' 'intoa mounted upona fourth shaft 21', the latter being also journaled within the casing 4 aforesaid. Anothercom'paratively large gear 22 is provided, saidl gear being mounted pinion 20 upon the shaft '21. and positionedfor meshing engagement' with a pinion 23 mounted upon a -fifth shaft. 24, likewise journaled within the casing 4. .Attached to the pinion 23 and rotatable therewith is a governor device 25, said device comprisingin addition to the arms and balls 26 a collar 28 the latter being mounted for sliding engagement upon the shaft 24, such slidin gmovement being controlled by the speed of rotation of the governor device. Arms 29 lenl and 27 respectively,v

are pivoted to the sliding collar 28 as indicated at 30, saidl arms being also pivoted as indicated at 31 `tovbrake shoes 32 in turn pivoted as at 33 to a rod 34 mounted for roe goi-ernor 25 and upon the rod 34 is so positioned With .respect to the casing 4 as to rotate Within a circular' opening 35 thereof, the wall 0f the opening forming a friction'surface against which the shoes of the brake'device are forced. Suitable means is provided for locking the rod 34 against sliding movement"4 -l upon the shaft 24 during` a sliding move# ment of the collar 28. v

In operation, should thej elevator (not tates, the Igovernor shown) descend at an abnormal' `rate of speed, the gears 11 and 13 by reason of their engagement with the teeth l() of the double rack bar 8 will be rotated at an abnormal rate of speed, said gears correspondingly rotating thecomparatively large gears 15 and 16, Rotation 'of gear i6 imparts a like movement to the pinion 1S, which in turn rotates vcomparatively large gear 19 whereby to in turn rotate pinion 2O into the teeth of which the teeth ofthe gear 19 mesh. The pinion 20 rotates comparatively large gear 22, and, as the said gear 22 is in mesh with pinion 23, the latter is rotated, by reason of the several pinions and gears, at an exceedingly high rate ofvspeed. As the pinion 23.10-

device 25 rotatesat a corresponding rate, causing it to slide'upon. shaft 24 and exert outward pressure upon shoes`l32. As shoes 32 are forced outwardly or into engagement withthe surface 35, it is apparent that the speed of rotation of the gears and pinions aforesaid is checked and, as certain of the said gears mesh with the stationary rack bar 8, a corresponding decrease in the rapidity of descent of the car is effected.

From the above, taken in connection with the laccompanying drawings, it will be 'noted that duplicate gear mechanism is arranged upon each side rangement preventing a stripping of the gears in the event of a sudden stopping of the elevator car when descending; that the entire safety appliance, with the exception of the rack bar 8, is movable bodily with the elevator car or cage; and1 thatby the vprovision ot the chain of gears above noted, the governor operating pinion 23 is rotated at an exceedingly high rate of speed" upon the rotation of the gears 11 andyl ata speed in excess of a predetermined rater ln reduction to. practic e,1 have found illustrated m that the form of my invention,

the above the drawings and referred to in of the rack bar 8, such ar Apoints 'relatively nasplii description, as the preferred embodiment, is

the most eiiicient and practical; yet realizing that the conditions concurrent with the' adoption of my device will necessarily vary, l desire to emphasize the fact .that various minor changes in proportion and arrangement of parts may be resorted to, when required, Without sacrificing any of the advantages of my` invention, asdened in the appended claims.`

Having thus fully describedmy invention, whatl claim as new and desire to secure by Letters" Patent, is

1. Centrifugal brake mechanism includ ing an annular brake engaging surface, a shaft having its axis concentric to said surface, a collar loose upon said shaft, a rod mounted on said shaft, a brake shoe pivotcdto themed, and arm connected to the collar and the bralce shoe to move said shoe into and out of braking relation with said surf face, governor mechanism mounted on the shaft to control movement of said collar, and means to rotate the shaft.

2. Centrifugal brake mechanism includ ing an annular brake engaging surface, a shaft having its axis extending concentric to saidsurface, a collar loose upon sail shaft, a rod -mounted on said shaft. to terminate adjacent and at diametrically opposite to said surface, a brake shoe pivoted to each rod terminal, arms conf necting thecollar and the respective brake shoes to move said shoes into and out of braking relation with said surface, governor mechanism mounted on the shaft to control movement of said collar, and means to rotate/stile shaft. f

ntestimony whereof l atlix my signature in presence of two Witnesses. Y

ALBERT C. COBB.,

'Witnesses J. R. EWLL,

EDWARD A. ELLIS.Y

details of construction, 

